Along our sandy roadsides there's a very common, dense and much-branched bush getting 12 feet or so high (3.6m). It's a native, different species of yellow-oleander, THEVETIA GAUMERI. You can see it below:

Its yellow, funnel-shaped flowers are very similar to the much-planted Yellow Oleander, as shown below:

Our sandy-road yellow-oleanders have fruits similar to those of the planted species, and when mature turn red as well. Nowadays they're still green, though, as seen below:

So, the neat thing about our wild yellow-oleander is that it's so similar to the famous, much-planted Yellow Oleander, but it's just a different species, one hardly anyone knows about. Our species specializes in coastal scrub from the Yucatan south to Costa Rica.

Both yellow-oleander species are member of the Dogbane Family, the Apocynaceae, and as is typical of that family they ooze milky, sticky latex when injured. Of course the Maya have noticed this and use the latex medicinally in many ways -- for everything from boils to snakebite, for holding cut skin together, for mange and inflamed skin, to keep down infection, on and on.